DESCRIPTION: (Applicant's Description) The purposed pathology/cell culture/DNA core has four distinct purposes and goals as follows: A) To acquire Kaposi's sarcoma, PEL and other clinical and tumor samples from a variety of sources including the AIDS Lymphoma Bank. To carry out pathological analysis and grading as well as virological characterization assays on these samples including histological staining. VIL6, Y1.1 and vCYC- D in situ hybridization (ISH), vIL6 and LANA immunohistochemistry (IHC) and DNA PCR for HHV-8, EBV, etc. The results will be used to attempt to correlate levels of viral gene expression with KS disease stages and to coordinate the distribution of appropriate selected samples to individual investigators who need to examine additional levels and patterns of gene expression. Where required Core B personnel will also assist with RT-PCR and in situ PCR or double-label techniques, etc. B) To supply all PPG investigators with uniform cultures of a variety of well characterized PEL/BCBL lymphoma cell lines and KS spindle cell lines, plus HHV-8-infected primary or immortalized endothelial cell cultures and control HUVEC, DMEC, or lymphocyte (PBMC) cell cultures. Each PEL cell culture sample will be characterized for HHV-8 and EBV genome copy number and inducibility to TPA and NBA at different passage numbers. C) To provide confirmed and characterized HHV-8 genomic and cDNA lambda phage or DNA reagents as needed to individual projects. Nearly 90 percent of our prototype BVBL-R(A1/P) DNA genome together with induced lytic cycle PEL cDNAs for nearly all of the HHV-8 genes mentioned in individual projects are available. D) To determine the LGS and RHS HHV-8 subtype (A,B,C or D and P,M or Q) of all clinical samples received for investigation as well as to accumulate a large library of representative genomes from U.S.A. and international sources for selective DNA sequencing to evaluate genetic variability within the specific genes of interest to individual PPG investigators.